CVE-2026-90306: ARM: 9481/2: breakpoint: CFI breakpoints only on demand

Severity: unknown
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-17 · updated 2026-10-19

Description

In the Linux kernel, the following vulnerability has been resolved: ARM: 9481/2: breakpoint: CFI breakpoints only on demand This removes the stub hw_breakpoint_cfi_handler() from ARM, making it not steal breakpoint type 0x03 (ARM_ENTRY_CFI_BREAKPOINT) unless CFI is actively used in the kernel. When not instrumenting with CFI, or when a breakpoint is issued in userspace, we fall through to return 1 from hw_breakpoint_pending() "unhandled fault" so userspace can make use of this breakpoint. Tested with LKDTM and this command line: echo CFI_FORWARD_PROTO > /sys/kernel/debug/provoke-crash/DIRECT still works as expected.

Affected products

Linux kernel: 6.10 — fixed in 7.3

How to fix

Upgrade to a fixed version: Linux kernel 7.3. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2026-90306 or the next vulnerability affects your stack